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List the uses of a transformer.

Important Questions on Consequences

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Physics>Change>Consequences>Transformer
A transformer is used to light a 100 W, 110  V lamp from a 220 V supply. If the supply current is 0.6 A, the efficiency of the transformer is
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Physics>Change>Consequences>Transformer

An ideal transformer has 500 and 5000 turn in primary and secondary windings, respectively. If the primary voltage is connected to a 6 V DC battery, then the secondary voltage is:

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Physics>Change>Consequences>Transformer
Which of the following remain constant in a transformer ?
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Physics>Change>Consequences>Transformer
What is the phenomenon involved in the working of transformer ?
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Physics>Change>Consequences>Transformer
A transformer having efficiency of 90% is working on 200 V and 3 kW power supply. If the current in the secondary coil is 6 A the voltage across the secondary coil and the current in the primary coil respectively are:
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Physics>Change>Consequences>Transformer
A step-down transformer has turn ratio 20:1. If 8 V is applied across 0.4 Ω secondary then the primary current will be
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Physics>Change>Consequences>Transformer
A step-up transformer operates on a  230 V line and a load current of 2 A. The ratio of primary and secondary windings is 1: 25 . Then the current in the primary is
 
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Physics>Change>Consequences>Transformer
 A step down transformer connected to an ac mains supply of 220 V is made to operate at 11 V, 44 W lamp. Ignoring power losses in the transformer, what is the current in the primary circuit?
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Physics>Change>Consequences>Transformer
A power transmission line feeds input power at 2300 V to a stepdown transformer with its primary windings having 4000 turns. What should be the number of turns in the secondary windings in order to get output power at 230 V?
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Physics>Change>Consequences>Transformer
A transformer operates at Vp=6kV on the primary side and supplies electric energy at VS=220V to a number of houses in a town. If the total power consumption of the town is 7.2kW, the current (in amperes) in the primary is
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Physics>Change>Consequences>Transformer

For the given circuit, comment on the type of transformer used :

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Physics>Change>Consequences>Transformer
A power transmission line feeds input power at 2300 V to a step-down transformer with its primary windings having 4000 turns giving the output power at 230 V. If the current in the primary coil of the transformer is 5 A and its efficiency is 90 %, the output current would be:
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Physics>Change>Consequences>Transformer
A transformer has efficiency 80%. It works at 5 kW and 150 V. If the secondary voltage is 240 V, the secondary current is
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Physics>Change>Consequences>Transformer
A common transistor radio set requires 12 V D.C. for its operation. The D.C. source is constructed by using a transformer and a rectifier circuit, which are operated at 220 V A.C. on standard domestic A.C. supply. The number of turns of secondary coil are 24, then the number of turns of primary are
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Physics>Change>Consequences>Transformer
A primary coil is connected with an AC source and a bulb is connected with the secondary coil. The voltage across the bulb is 6.0 V and the current through the bulb is 0.4 A, The turns ratio is 5:1( Np:Ns=5:1). Calculate the current in the primary coil.
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Physics>Change>Consequences>Transformer
A transformer is used to glow a 140 W-240 V bulb at 240 V AC. If current in the primary coil is 0.7 A, then the efficiency of the transformer is
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Physics>Change>Consequences>Transformer
How much current is drawn by the primary coil of a transformer, which steps down 220 V to 55 V to operate a device with an impedance of 275Ω?
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Physics>Change>Consequences>Transformer
A current of 6 A is flowing at 220 V in the primary coil of a transformer. If the voltage produced in the secondary coil is 1100 V and 40% of power is lost, then the current in the secondary coil will be:
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Physics>Change>Consequences>Transformer
A transformer consisting of 300 turns in the primary and 150 turns in the secondary gives output power of  2.2 kW . If the current in the secondary coil is  10 A , then the input voltage and current in the primary coil are:
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Physics>Change>Consequences>Transformer
A power transmission line feeds input power at 2300 V to a step down transformer with its primary windings having 4000 turns. The output power is delivered at 230 V by the transformer. If the current in the primary of the transformer is 5 A and its efficiency is 90 %, the output current would be: